Improvement in the manufacture of sheet-iron



UNITED STATES PATIENT DAVID A. MORRIS, OF PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN THE MANUFACTURE OF SHEET-IRON.

Specification forming part of Letters Patent No. 31,184, dated January 22, 1861.

-rolled to the proper size and weight with a thin uniform coat of ferrate of iron, commonly called black oxide-iron scale. Ferrate of iron is acompound of protoxide and scsqui oxide, according to the chemical configuration FeL e:FeO+2Fe,O, the former being the base and the latter the acid. Now, by converting this ferrate of iron into a protocarbide of iron (FcOO) we have a compound that is almost as inoorrodible as platina or gold, and capable of receiving a very fine polish. To effect this change in the nature of the ferrate of iron, and at the same time produce the finish desired, I manipulate the iron in manner as follows, viz: Taking the sheets of iron with the ferrate of iron on them, I apply a coat of coal-oil or petroleum. (Carbon in any other convenient form will do as well.) Then I place as many of the sheets thus preparedsay twenty-five or thirty-in a straight-sided panlike case, a section of which appears thusr Then, after puting on another sheet to constitute the lid, I turn over the edges of the case, thereby forming a close box, a section of which appears thus:

Then I place the whole in ainuffle, to be heated to about 900 Fahrenheit. Then I hammerthe packease and sheets-with a large faced steam-hammer, which should strike a blow of two hundred and fifty to threehundred pounds to the square inch of the hammer-face, and should run at least one hundred blows per. minute. If the hammering is continued until the iron is cool enough to bear the hand on it, it will have received a beautiful glossy enamel of the character above described, and so thoroughly incorporated with the iron'that it may be worked into intricate shapes without scaling off.

Hammering hardens the iron, so that it re quires annealing afterward, and it is difficult to hammer a large package of sheets entirely straight. They are likely to be more or less buckled. I therefore arrange a number of sheets in a case the same as for hammering,

V and as soon as the packing is properlyheated,

which can be done without effecting the polish of the enamel, Iplace it in a powerful press to cool. By this means I anneal sheet-iron' much quicker and cheaper than it is done by the only other method now in use, and am enabled at the same time to remove all kinks or buckle.

What I claim as my invention, and desire to secure by Letters Patent, is

The application of carbonaceous material prior to heating the iron, (without removing the iron scale or black oxide from the surface of the sheets,) and for thepurpose specified.

- D. A. MORRIS.

Witnesses:

THos. OWs'roN, J AS. MQGARGILL. 

